Workflow for batch rendering in the same scene with different cameras
Oh, never mind. I would rather use the old approach with Python script to change all the render settings like this

import bpy

def RenderAllScenes():
    for scene in bpy.data.scenes:
        bpy.ops.render.render(scene = scene.name, animation=True)

def CommonSetup():
    for scene in bpy.data.scenes:
        scene.render.resolution_x = 1920
        scene.render.resolution_y = 1080 
        scene.render.tile_x = 256
        scene.render.tile_y = 256
    return

def Setup(resolutionPercentage):
    for scene in bpy.data.scenes:
        CommonSetup()
        scene.render.resolution_percentage = resolutionPercentage


In Blender's interactive console I can then import renderSettings.py then renderSettings.Setup(50), etc.